Apparatus for making a concrete column form

ABSTRACT

This invention relates to forms for molding concrete columns and more particularly to a method and apparatus for producing a form for pouring concrete columns of any desired cross-sectional shape.

United States Patent 11 1 Cannon et ai.

3,751,196 Aug. 7, 1973 l l l l APPARATUS FOR MAKING A CONCRETE [COLUMN FORM inventors: David C. Cannon; Walter E.

Johnson; Richard W. Turnage, all of Hartsville, S.C.

Assignee: Sonoco Products Company, Hartsville, S.C.

Filed: Dec. 9, 1970 Appl. No.: 96,497

Related U.S. Application Data Division of Ser. No. 727,967, May 9, i968,

abandoned.

US. Cl 425/4, 264/45, 425/110, 425/179 Int. Cl B29d 27/04 Field of Search 425/4, 110, 175,

[56] References Cited UNITED STATES PATENTS 3,537,131 11/1970 Kracht et al. 425/4 3,301,926 1/1967 Reiland 425/817 X 2,707,804 5/1955 Thornburg 425/4 X Primary Examiner-H. A. Kilby, Jr. Att0rney-T. Russell Foster [57] ABSTRACT This invention relates to forms for molding concrete columns and more particularly to a method and apparatus for producing a form for pouring concrete col-.

umns of any desired cross-sectional shape.

6 Claims, 14 Drawing Figures PATENIED 7975 SHEET 1 BF 5 FIG. 4A

I a a w v I z I l l r a I v I P! z z z w A I w z z I r FIG. 3

FIG.

NON

ATTORNEY I PATENIED AUG 7975 RICHARD W. T

URNAG ATTORNEY PAIENIEO A116 SHEET IUFS INVENTORS: DAVID C. CANNON WALTER E- JOHNSON RICHARD W. TURNAGE ATTORNEY PATENTED AUG 7 SHEET 5 0F 5 FIG. ll

.N m 06. N w m N T wmw m A D D w Am DWR Y B APPARATUS FOR MAKING A CONCRETE COLUMN FORM This application is a division of application Ser. No. 727,967, filed May 9, 1968, now abandoned for continuation as Ser. No. l40,6l9.

In the construction of buildings, bridges, and other structures, concrete columns are frequently incorporated as component parts of the structures for support and the like. Such concrete columns, which are generally reinforced with metal rods, etc., are generally formed by pouring concrete into a suitable form and permitting the concrete to harden following which the form is removed. Many of the poured concrete columns installed under present day practices are of circular cross-sectional shape and utilize tubular forms such as a heavy wall, spirally wound paper tube, the inner surface of which is coated with a suitable release material such as. is shown in U. S. Pat. No. 2,677,165. Such concrete columns formed today are frequently of considerable length and the pressure of the poured concrete subjects such forms to considerable stress which can cause distortion of the form and a resultant improperly formed column. However, a form of circular cross-sectional shape distributes such concrete stresses efficiently to produce a relatively smooth and uniform concrete column. As is well known, such paper tube forms are generally for one-time use as they are destroyed during the stripping operation.

Although concrete columns of circular crosssectional shape or round columns generally produce the desired architectural results, it is frequently desirable to provide concrete columns having crosssectional shapes which are other than round such as square, polygonal and the like for asethetic reasons, limitations of space, etc. However, it is recognized that it is more difficult to uniformly distribute the stresses produced by the poured concrete in forms for columns which are non-circular in cross-sectional shape and distortion of the form with attendant distortion of the resulting column frequently results. Some success has been achieved in producing a concrete column of noncircular cross-sectional shape by the use of reusable metal forms, articulated panels, etc., such as shown in U. S. Pat. No. 2,873,503. However, such non-circular concrete columns still do not have the desired appearance in comparison with the circular column and considerably more time and labor is required with attendant higher costs in setting up such non-circular column forms. Furthermore, the initial cost of such noncircular column forms is generally quite high and the rough handling to which such forms are subjected causes rapid deterioration and loss with prolonged use.

Accordingly, a primary object of this invention is to provide a new and novel form for forming concrete columns.

Another object of this invention is to provide a new and novel method of producing such a concrete column form.

A further object of this invention is to provide a new and novel apparatus for producing such a concrete column form.

Still another object of this invention is to provide a new and novel concrete column form which permits the formation of concrete columns having any desired cross-sectional shape such as circular, polygonal, square and the like.

A still further object of this invention is to provide a new and novel concrete column form for forming concrete columns of any desired cross-sectional shape which utilizes inexpensive, readily available material, which may be manufactured in a simple and easy manner and at a high production rate and which is of low initial cost so as to economically permit one-time use.

Still another object of this invention is to provide a new and novel concrete column form for forming concrete columns of any desired cross-sectional shape which is lightweight and rugged in construction the inner surface of which permits the formation of a smooth uniform exterior on the poured concrete column and at the same time permits ready stripping of the form after hardening of the poured concrete column.

This invention further contemplates the provision of a new and novel method and apparatus for forming such a concrete column form which permits the production of such forms of any desired length and which may be utilized at a high production rate to produce a form of relatively low cost for one-time use.

Other objects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings.

The objects stated above and other related objects in this invention are accomplished by the provision of a form for forming concrete columns of any desired cross-sectional shape. The form includes a tubular member such as a paper tube on the inner wall of which is supported a liner of expanded plastic foam material having a central bore the cross-sectional shape of which corresponds to the cross-sectional shape of the concrete column to be formed. The method and apparatus of the invention for forming such a form includes a mandrel around which is releasably clamped the tubular member to form an annular clearance space which is filled with expansible plastic material. The expansible plastic material is expanded to fill the clearance space with expanded plastic foam material with the resulting form being subsequently removed from the mandrel.

The novel features which are believed to be characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation may be best understood by reference to the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of one embodiment of a form constructed in accordance with the invention;

FIG. 2 is a sectional view taken substantially along line 2--2 of FIG. 1 in the direction of the arrows;.

FIG. 2A is a sectional view similar to FIG. 2 showing a form for producing a generally square beaded column;

FIG. 3 is a view similar to FIG. 1 showing another embodiment of the form of the invention;

FIG. 4 is asectional view taken substantially along line 4-4 of FIG. 3;

FIG. 4A is a sectional view similar to FIG. 4 showing a form for producing a generally circular fluted column; 7

FIG. 5 is a perspective view of the apparatus of the invention for forming the form of FIGS. 1, 2;

. FIG. 6 is a schematic sectional view of the apparatus of FIG. 5 in one operating position;

FIG. 7 is a view similar to FIG. 6 showing the apparatus in another operating position;

FIG. 8 is a view similar to FIGS. 6, 7 showing the apparatus of the invention in another operating position;

FIG. 9 is a view similar to FIGS. 6, 7 and 8 showing the apparatus of the invention in still another operating position;

FIG. 10 is an enlarged sectional view with the medial portion broken away of the apparatus as shown in FIG. 8;

FIG. 11 is a sectional view taken substantially along line 11-11 of FIG. 10 in the direction of the arrows;

and

FIG. 12 is a sectional view taken substantially along line l2l2 of FIG. 10 is the direction of the arrows.

Referring now to the drawings and to FIGS. 1, 2 and 2A in particular, there is shown one embodiment of the form of the invention for forming concrete columns which are substantially square in cross-sectional shape. More specifically, the form of FIGS. 1, 2 and 2A are designated generally by the letter F and includes a tubular member 11 such as a paper tube. The tubular member or paper tube 11 is preferably a multi-ply spirally wound paper tube of the well-known construction, having on its outer surface a spiral seam 12.

The tube 11 is provided with a relatively heavy wall thickness for strength and rigidity this wall thickness being determined as is well-known by the number of plies of paper forming the spirally wound tube 11. The tube 11 has an inner surface 13 on which is supported in intimate contact therewith a liner 14 of rigid, expanded plastic foam material. Although any suitable plastic foam material may be utilized, it has been found that the outstanding results of the invention are obtained with the use of polystyrene beads of any commercially available type which have been expanded by heating or the like to form the plastic foam material constituting the liner 14 as will be explained hereinafter.

The liner 14 has a central bore 16 the cross-sectional shape of which corresponds to the cross-sectional shape of the concrete column to be formed. In the embodiment of FIGS. 1, 2, the liner 14 of the form F has a central bore 16 which is substantially square in crosssectional shape to form a square concrete column. Preferably, the inner wall 17 of the liner 14 which defines the central bore 16 has chamfered corners 17a to avoid the production of sharp corners on the resulting concrete column.

Of even more significance and as contributing to the new and unexpected results of the invention, the liner inner surface 17 is a hard, densified layer of the expanded plastic foam material forming the liner 14, the remaining portions of the foam material of the liner having less density. This hard densified surface layer 17, as will be explained hereinafter, provides a durable smooth surface for the liner 14 which not only resists the destructive effects of the concrete poured within the bore 16 but which produces a smooth uniform surface on the resulting concrete column. Also, the liner [4 is preferably provided with one or more longitudinally extending spaces or bores 18 formed in any suitable shape and in the manner explained hereinafter. In the illustrated embodiment of FIG. 2, the bores 18 which extend through the liner 14 intermediate the liner surface 17 and the tubular member 11 are preferably round as shown.

Referring now to FIGS. 3, 4 and 4A, there is shown another embodiment of the form of the invention which is designated generally by the letter F and wherein like numerals are used to identify like parts with the prime notation added. As in the embodiment of FIGS. 1, 2 and 2A, the form F includes a paper tube II having outer spiral seams 12', the inner wall 13 of the tube 11' has supported thereon a liner l4 similarly formed of expanded plastic foam material and provided with an inner wall 17 defining a central bore 16' which is circular in cross-sectional shape. The form F is therefore used to form concrete columns which are circular in cross-sectional shape and as in the embodiment of FIGS. 1, 2 and 2A, a hard, densified layer of expanded plastic foam material is formed on the surface 17 for the purposes previously discussed.

Similarly, the liner 14' is provided with a plurality of longitudinally extending bores 18' preferably circumferentially spaced as shown in FIGS. 4, 4A as in the previous embodiment. It should be understood that although the central bores 16, 16 of the forms F, F are square and circular respectively in cross-sectional shape, the central bores may be formed of any desired cross-sectional shape such as polygonal, rectangular, oval, etc., as the rigidity of the plastic foam liners together with the hard densified surfaces on the inner wall of the plastic foam liners permit the formation of smooth surfaced columns which are uniform in crosssectional shape throughout their length.

Apparatus is provided in accordance with the invention for forming the forms F, F. Referring now to FIGS. 5-12, there is shown apparatus constructed in accordance with the invention for carrying out the novel method of the invention for producing the forms F, F. As generally illustrative of the apparatus of the invention and referring now to FIG. 5, there is provided an elongated, rigid mandrel designated generally by the numeral 21 having a cross-sectional shape corresponding to the cross-sectional shape of the concrete column to be formed with the form of the invention. In the illustrated embodiment, the mandrel 21 is substantially square with chamfered corners 21a to produce the form F of FIGS. 1, 2. The mandrel 21 is suitably secured by welding or the like to a base plate 23 suitably supported in an elevated position on means such as legs and feet 24.

Means are provided for releasably clamping a tubular member such as the paper tube 11 in radially spaced, concentric relationship with the mandrel 21 to form an annular clearance space 26 as best shown in FIGS. 7 and 10, between the outer surface 27 of the mandrel 21 and the inner wall I3 of the tube 11. More specifically, a plurality of upstanding guide rods 25 which in the illustrated embodiment are three in number are suitably secured at their lower ends adjacent tbe peripheral edge of the base plate 23 as shown in FIG. 5, which slidably accommodate guide sleeves 29 arranged in similarly spaced relationship between upper and lower plates 31, 32. The upper and lower plates 31, 32 together with the guide sleeves 29 constitute an assembly generally indicated at 33 and are secured together as a unit for reciprocating vertical movement as indicated by the double arrow I of FIG. 5 between the lowermost position of FIG. 7 and the uppermost position of FIG. 9.

Suitable means such as a hoist 34 are provided for raising and lowering the assembly 33 on the guide rods 25 which, in the illustrated embodiment, include a hoist 34 preferably driven by means such as an electric motor 36 and mounted in any suitable manner adjacent the upper ends of the guide rods 25 as shown best in FIGS. 6-9. The hoist 34 includes a cable 37 suitably attached to the upper plate 31. In the illustrated embodiment, the lower end of the cable 37 is attached to the housing of a fluid pressure actuated cylinder 38 secured to the upper surface of the upper plate 31 as shown best in FIG. 5 and having a piston 39 extending below the undersurface of the upper plate 31 through va suitable opening 41 in plate 31. The lower end of the Preferably a plurality of guide members 43, four being utilized in the illustrated embodiment, which are secured to the upper plate 31. The guides 43 include tubular housings 44 having rods 46 slidably movable therein which extend through the upper plate 31 with the lower ends in engagement with the clamping head 42 to maintain the head 42 level as it moves vertically between the illustrated positions of FIGS. 6, 7.

Means are also provided for closing the ends of the clearance space 26. More specifically, the lower plate 32 is provided with a centrally located, circularly shaped portion of reduced thickness having ashoulder 51 and a ledge 52 defining an opening 53 for receiving the mandrel 21 in closely fitting relationship as shown in FIGS. 7, 8 and 10. In the illustrated embodiment of FIG. 5, the opening 53 is square to correspond to the square cross-sectional shape of the mandrel 21 and the circular shape of the opening in the base plate 32 defined by the shoulder 51 is of a diameter for snugly accommodating the lower end of the tube 11 as also shown best in FIG. 10.

As shown best in FIG. 6, the paper tube 11 is positioned between the upper and lower plates 31, 32 with its lower end within the opening in the lower plate 32 defined by the shoulder 51 and the clamping head 42 in the uppermost position adjacent the underside of the upper plate 31. The clamping head 42 is then moved downwardly by means of the piston 39 by fluid pressure actuation of the cylinder 38 to clamp the tube 11 securely between the lower plate 32 and the clamping head 42, the clamping head being maintained in a horizontal plane as it moves into clamping engagement with the upper end of the tube 11 by means of the guides 46. The hoist 34 may then be actuated to lower the clamping assembly 33 into its lowermost position as shown in FIG. 7 so thatthe tube 11 together with the mandrel 21 defines the annular clearance space 26, the tube being clamped securely in this position.

Means are provided for introducing an expansible plastic material into the clearance space 26. In the illustrated embodiment, such expansible plastic material may be of any conventional type such as commercially available beads of plastic material such as polystyrene which when heated expand to form a rigid, plastic foam material. More specifically, an opening 56, FIGS. 5, 6 and 7, is provided in the clamping head 42 which communicates with the clearance space 26 and which is provided with a suitable cap 57 for opening and closing the passage 56. Thus, when the tube 11- is positioned in clamped relationship around the mandrel 21 in the position illustrated in FIG. 7, the cap 57 may be removed and polystyrene beads or the likesuitably introduced into the clearance space 26. After the clearance space 26 has been filled with a predetermined quantity of beads sufficient when expanded to completely fill the clearance space 26, the passage 56 is then closed by replacing the cap 57.

Means are provided for expanding the expansible plastic material in the clearance space 26 to fill the clearance space with expanded plastic foam material which expanded material designated by the numeral 58, FIGS. 8 and 9, forms the liner 14 of the form F shown in FIGS. 1, 2. More specifically, chambers 61, 62 are provided on the underside of the base plate 23 as shown best in FIG. 10. Chambers 61 and 62 are formed by a bottom wall 63 and inner and outer annular walls 64, 66 respectively. A plurality of upstanding conduits are positioned within the clearance space 26, four of such conduits 71 being provided in circumferentially spaced relationship as shown best in FIG. 11. The side wall of each of the tubular conduits 71 is provided with suitably spaced perforations 72 and the conduits 71 are supported on the base plate 23 intermediate the outer surface 27 of the mandrel 21 and the the inner surface 13 of the tube 11 in the clamped position of FIG. 10 with its lower end 73 in communication with the chamber 62.

The upper ends 74 of the conduits are closed and are arranged to be received within corresponding recesses 76 in the clamping head 42 in the clamped position of the tube 11 as shown best in FIG. 10. The chamber 62 communicates through a conduit 77 with a suitable source of steam so that steam introduced into the chamber 62 through the conduits 77 travels in the direction of the arrows S into the lower end 73 of the conduits 71 and through the perforations 72 into the annular space 26.

In a similar manner the conduits 77 may be connected to a source of cooling fluid such as water by conventional means (not shown) so that water may be similarly introduced into the annular space 26 through the conduit perforations 72. An outlet pipe 78 is positioned within the conduits 71 in co-axial relationship therewith as shown in FIG. 10 and extends through the chamber 62 and through the bottom wall 63 for communicating with fluid disposal means through suitable means such as a hose 79. Thus, both condensate from the steam flowing within the conduits 71 and the cooling water flowing through the conduits 71 enter the upper end of the outlet pipe 78 and flow in the direction of the arrows 0 out of the apparatus as shown.

Means are provided for heating the mandrel 21 to form a hard, densified surface layer on the expanded plastic material adjacent the outer surface 27 of the mandrel. More specifically, the mandrel 21 has a side wall 81 of square cross-sectional shape as described above and a top wall 82 defining an interior 83 as shown best in FIG. 10. The mandrel side wall 81 and top wall 82 are preferably formed of metal and is reinforced internally by cross members 84, 85 suitably secured to the mandrel side wall 81 as shown best in FIG.

A plurality of upstanding conduits 86 are positioned within the mandrel interior 83 being supported on the base plate 23 as shown with their lower ends 87 in communication with the chamber 61. The chamber 61 communicates with a source of steam and cooling water (not shown) through a conduit 88 so that steam may be introduced into the interim-'83 of the mandrel 21 in the direction of the arrows T through the upper end 89 of the supply pipe 86.

In order to remove the condensate and cooling water from the mandrel interior 83, and outlet pipe 91 is provided which extends centrally through the base plate 23 and the bottom wall 63 as shown with its upper end 92 in communication with the mandrel interior 83. Thus, both condensate and cooling water drains out of the mandrel interior 83 in the direction of the arrows W for discharge in any suitable manner through suitable means such as a discharge line 93.

In carrying out the method of the invention with the novel apparatus described above to produce the form F, a tube 11 is positioned within the clamping assembly 33 as shown in FIG. 6 with the clamping assembly being moved to the elevated position as shown by means of the hoist 34. The fluid pressure cylinder 38 is then actuated to move the clamping head 42 downwardly so that the tube 11 is clamped as shown in FIG. 7 between the lower plate 32 and the clamping head 42.

The clamping assembly 33 may then be moved downwardly in the position of FIG. 7, the mandrel 21 being accommodated within the opening 53 in the bottom plate 31 and the supply conduits 71 being received through the spaced openings 75 in the bottom plate 32 until the upper ends 74 are received within the recesses 76 of the clamping head 42. A predetermined quantity of beads of expansible plastic material is then introduced into the clearance space 26 through the opening 26 in the clamping head which is subsequently sealed by the cap 57.

The plastic material in the clearance space 26 is then expanded by the introduction of steam through the conduits 71 and through the perforations 72 whereupon the plastic material expands to form the rigid plastic foam liner 14 as shown in FIGS. 2, 9 supported on the inner surface 13 of the tube 11. The bores 18 in the expanded plastic foam liner 14 remain after removal of the conduits 71. In addition, the mandrel 21 is heated by the introduction of steam through the supply pipes 86 so as to heat the mandrel side wall'8l whereupon a hard, densified layer of plastic foam material is formed on the inner surface 17 of the liner 14 which is in contact with the mandrel outer surface 27.

Subsequently, cooling fluid is introduced into the conduit 71 and into the supply pipes 86 so that the plastic foam material adjacent the conduits 71 and mandrel outer surface 27 is cooled, the cooling water flowing out the drain pipes 77 and 91 respectively. The resulting form F may then be removed from the apparatus of the invention by elevating the clamping assembly 23 at which time the tube 11 and liner 14 supported thereon strips from the mandrel 21. Subsequent elevation of the clamping head 42 then permits the form F to be removed from the apparatus for subsequent use.

While there has been described what at present is considered to be the preferred embodiment of the invention, it will be understood by those skilled in the art that various changes and modifications may be madetherein without departing from the invention and, therefore, it is the aim of the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

Having thus described the invention, what is claime 1. Apparatus for making a concrete column form comprising, in combination, an elongated, rigid mandrel having a cross-sectional shape corresponding to the cross-sectional shape of the concrete column to be formed with said form, means for releasably clamping a tubular member in radially spaced, concentric relationship with said mandrel to form an annular clearance space between the outer surface of said mandrel and the inner wall of said tubular member, means for closing the ends of said clearance space, means for introducing expansible plastic material into said clearance space, means for expanding said expansible plastic material in said clearance space to fill said clearance space with expanded plastic foam material and means for removing said tubular member and said expanded plastic foam material from said mandrel to thereby provide said concrete column form.

2. Apparatus in accordance with claim 1 wherein said means for expanding said expansible plastic material includes means for heating said plastic material in said clearance space and including means for heating said mandrel to form a hard, densified surface layer on the expanded plastic foam material adjacent the outer surface of said mandrel.

3. Apparatus in accordance with claim 2 including means for cooling said mandrel and means for cooling said expanded plastic foam material.

4. Apparatus in accordance with claim 2 wherein said means for heating said expansible plastic material include a plurality of conduits having perforations extending longitudinally within said clearance space, means for supplying steam to said conduits to thereby introduce steam through said perforations into said plastic material.

5. Apparatus in accordance with claim 4 including means for supplying a cooling fluid to said conduits for cooling said expanded foam material.

6. Apparatus in accordance with claim 5 wherein said mandrel is of tubular shape having a side wall defining an interior, and wherein said means for heating said mandrel includes means for introducing steam into said mandrel interior and including means for introducing a cooling fluid into said mandrel interior for cooling said heated mandrel.

* k I I 

1. Apparatus for making a concrete column form comprising, in combination, an elongated, rigid mandrel having a cross-sectional shape corresponding to the cross-sectional shape of the concrete column to be formed with said form, means for releasably clamping a tubular member in radially spaced, concentric relationship with said mandrel to form an annular clearance space between the outer surface of said mandrel and the inner wall of said tubular member, means for closing the ends of said clearance space, means for introducing expansible plastic material into said clearance space, means for expanding said expansible plastic material in said clearance space to fill said clearance space with expanded plastic foam material and means for removing said tubular member and said expanded plastic foam material from said mandrel to thereby provide said concrete column form.
 2. Apparatus in accordance with claim 1 wherein said means for expanding said expansible plastic material includes means for heating said plastic material in said clearance space and including means for heating said mandrel to form a hard, densified surface layer on the expanded plastic foam material adjacent the outer surface of said mandrel.
 3. Apparatus in accordance with claim 2 including means for cooling said mandrel and means for cooling said expanded plastic foam material.
 4. Apparatus in accordance with claim 2 wherein said means for heating said expansible plastic material include a plurality of conduits having perforations extending longitudinally within said clearance space, means for supplying steam to said conduits to thereby introduce steam through said perforations into said plastic material.
 5. Apparatus in accordance with claim 4 including means for supplying a cooling fluid to said conduits for cooling said expanded foam material.
 6. Apparatus in accordance with claim 5 wherein said mandrel is of tubular shape having a side wall defining an interior, and wherein said means for heating said mandrel includes means for introducing steam into said mandrel interior and including means for introducing a cooling fluid into said mandrel interior for cooling said heated mandrel. 